DESCRIPTION:(Adapted from the applicant's abstract) This is a competitive renewal proposal from an established investigator to continue his previous work analyzing the role of the RIIbeta protein kinase A gene product in the regulation of body weight and metabolism. During the previous funded period the PI demonstrated that genetically ablating RIIbeta resulted in mice which were lean and resisted diet-induced obesity. The proposed studies would clarify the mechanisms mediating these effects, by examining the role of UCP-1 in mediating the lean phenotype of RIIbeta knockouts, assessing the role of RIIbeta in specific tissues, determining the role of high-affinity scaffolding proteins in mediating effects of RIIbeta, and determining the role of PKA activity in mediating effects of the RIIbeta knockout.